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BaseRepresentation
bin10011101
312211
42131
51112
6421
7313
oct235
9184
10157
11133
12111
13c1
14b3
15a7
hex9d

157 has 2 divisors, whose sum is σ = 158. Its totient is φ = 156.

The previous prime is 151. The next prime is 163. The reversal of 157 is 751.

Subtracting from 157 its sum of digits (13), we obtain a square (144 = 122).

It can be divided in two parts, 15 and 7, that multiplied together give a triangular number (105 = T14).

157 is nontrivially palindromic in base 7 and base 12.

It is a balanced prime because it is at equal distance from previous prime (151) and next prime (163).

It can be written as a sum of positive squares in only one way, i.e., 121 + 36 = 11^2 + 6^2 .

It is an emirp because it is prime and its reverse (751) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 157 - 23 = 149 is a prime.

It is a Chen prime.

It is the 13-th Hogben number.

157 is an undulating number in base 7.

157 is a nontrivial repdigit in base 12.

It is a plaindrome in base 5, base 8, base 10, base 11, base 12 and base 16.

It is a nialpdrome in base 6, base 12, base 13, base 14 and base 15.

It is a zygodrome in base 12.

It is a congruent number.

It is a nontrivial repunit in base 12.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 78 + 79.

It is an arithmetic number, because the mean of its divisors is an integer number (79).

2157 is an apocalyptic number.

It is an amenable number.

157 is a deficient number, since it is larger than the sum of its proper divisors (1).

157 is an equidigital number, since it uses as much as digits as its factorization.

157 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 35, while the sum is 13.

The square root of 157 is about 12.5299640861. The cubic root of 157 is about 5.3946907121.

The spelling of 157 in words is "one hundred fifty-seven", and thus it is an aban number.